The aims of the project are to determine fundamental response characteristics of man to small doses of carbon monoxide (CO), as these relate to processing of information of incoming sensory stimuli and man's interaction with his environment, and to continue development of techniques for the evaluation of effects of small doses of various toxic agents on human functioning. The practical objective of the research is to assess the extent of impairment in human functioning (both psychological and physiological) from exposure to CO and thus aid in establishing air quality standards relevant to industrial expsoures and consequent performance, safety, and health. The methods which are being developed are applicable to a variety of toxic industrial and pharmacological agents. The main focus of the research is on CO effects on visual functions with special emphasis on peripheral vision using both a simple detection task and a more complex dual task which requires performance on a central task while monitoring simultaneously occurring peripheral stimuli. Multiple measures are used to evaluate the effects of CO within the framework of information processing by human subjects. These measures include behavioral responses, electrophysiological activity (EEG and evoked potentials), and eye movements, when each is applicable to the testing situation. The amount of CO present in the blood is determined by estimating the carboxyhemoglobin (COHb) levels present during all testing using both blood samples and breath samples.